Method and apparatus for distributing viscous liquids and heavy slurries



Nov. 17, 1953 J. W. ANGSTADT METHOD AND APPARATUS FOR DISTRIBUTINGVISCOUS LIQUIDS AND HEAVY SLURRIES Filed June 8, 1950 7 INVENTOR.

WW mark-a m Fo MJM Patented Nov. 17, 1953 METHOD AND APPARATUS FORDISTRIBUT- ING VISCOUS LIQUIDS AND HEAVY SLUR- RIES John WaltonAngstadt, Kenmore, N. Y., assignor,

by mesne assignments, to Blaw-Knox Company, Pittsburgh, Pa., acorporation of Delaware Application June 8, 1950, Serial No. 166,832

7 Claims.

This invention relates to a method and apparatus for distributingviscous liquids and heavy slurries and is more particularly shown asused in conjunction with an atmosphere double drum dryer, although theinvention can be employed wherever it is desired to distribute suchviscous liquids or heavy slurries uniformly over an extensive area,particularly along an extended line, such as in distributing liquid soapuniformly the full length of a flaker drum in chilling the soap,

or distributing molasses uniformly into a mixer or blender or into ascrew conveyer through which other materials are being moved.

In distributing a regulated amount of liquid uniformly over an extendeddistance a number of difficulties develop when the liquid to bedistributed has a considerable viscosity or contains solids insuspension. These difficulties are even more pronounced if the liquid isto be distributed over the surface of a set of heated revolving drums asin the case of a double drum dryer and the invention will be moreparticularly described in conjunction with a double drum atmosphericdryer.

The liquid fed to a double drum dryer not only should be distributed asevenly as possible over the length of the drums, but has to be limitedto the amount which the dryer is capable of handling. A simpleperforated feed pipe or overflow trough is entirely satisfactory if theliquid has a low viscosity so that the liquid dropping into or enteringthe pool held between the drums immediately mixes with the liquid in thepool and establishes a uniform level of the pool and a uniform conditionof the liquid contained throughout the entire length of the pool.

Reciprocating feeding devices traveling along the pool contained betweenthe drums of an atmospheric double drum dryer have been employed. suchas a reciprocating carriage or the end of the pool between the drums itslows up, stops for a moment, and then increases in speed on startingthe reverse stroke. The rate of feed Thus, as

g, centers of the drums. If this excess feed liquid delivered at theends of the pool between the drums mixes quickly with the liquid at thecenter of the pool, the operation of these reciprocating feeding devicesis satisfactory. If, however, the liquid is of such viscosity that itdoes not luickly mix with the liquid in the pool, the 1iqdid in the poolat the centers of the drums becomes more concentrated whereby arelatively dilute film is applied to the ends of the drums as comparedwith the centers thereof. This results in highly undesirable unevendrying conditions and which isespecially pronounced if the feed liquidis of high viscosity or is a heavy slurry. In addition, such areciprocating feeding device does not deposit liquid at uniformintervals except in the exact center. Away from the center intervals arealternately longer and shorter depending on the distance from the ends.

Feeding a heavy liquid or slurry through a perforated pipe or a seriesof small apertures of fixed dimension is not satisfactory because offrequent stoppages of these small openings thereby again resulting innon-uniformity of feed of the liquid from one end of the pool to I theother as well as diminishing the rate of the by the reciprocatingcarriage for pendulum feed pipe usually is constant and hence thereduced rate of travel at the ends of the drums results in a greateramount of liquid being delivered at pendulum feed pipe shown in theLavett Patent .the ends of the drums as compared with the and apparatusforfeeding viscous liquids and heavy slurries which will operate withsuch umformity for an indefinite period of time andin particular willnot clog or deliver the liquid at a diminishing rate.

Another object is to provide such a distributing feeder for viscousliquids and heavy slurries which is adjustable in its action while inoperation and in particular in which the size of the large openingsthrough which the liquid or slurry is discharged can be adjusted whilethe feeder is in operation.

Another object of the invention is to provide such feeder which does notrequire an elaborate rotary joint as has been found frequently to be asource of leakage.

Another object of the invention is to provide such a feeder which issanitary and extremely easy to clean.

Another objectis to provide such a. feeder which is simple andinexpensive in construction and is reliable in operation.

Other objects and advantages of the invention will appear from thefollowing description and drawings in which:

Fig. 1 is an end view, partly in section, showing a conventional doubledrum atmospheric dryer having a hood through which the vapors are ventedand equipped with a distributing feeder for viscous liquid and heavyslurries embodying the present invention.

Fig. 2 is a vertical sectional view taken generally on line :2-2, Fig.1.

Fig. 3 is an enlarged vertical section, partly in elevation, takenthrough the distributing feeder embodying the present invention.

Fig. 4 is a further enlarged vertical transverse sectional view taken online 44, Fig. 3.

Fig. 5 is a view similar to Fig. 3 and showing a modified form of theinvention.

The invention is illustrated in conjunction with an atmospheric doubledrum dryer which can be of any suitable construction and is illustratedin simplified form as composed of a pair of hollow end heads 8 and 'l inwhich the opposite ends of the shafts 8 and 9 of the pair of drums I andH are journalled. The drums are provided with the usual end boards I2and [3 which confine the liquid as a body or pool in the trough orvalley 14 between the drums, and the drums are illustrated as movingdownwardly at their point of closest approach to remove the viscousliquid or heavy slurries from the body 5 as films or layers which dry orharden on the under surfaces of the drums I0 and II and the driedmaterial scraped off by doctor knives |5, although it will be understoodthat the drums could rotate in the opposite direction, that is, upwardlyat their point of closest approach in which case the doctor knives l 5would be located on the lower periphery of the drums. The drums aresupplied with steam or other heating medium by any suitable means (notshown) and are rotated from a main drive shaft l8 which extends throughand is journalled in the end head 6 and has fast thereto, within thisend head, a pinion I8. This pinion l8 drives a large gear |9 on theshaft 8, this last gear meshing with a similar gear (not shown) on theshaft 9 so that the drums l0 and H are driven at the same speed. Thevapors generated during drying on the drums Ill and II are shown asvented from an overhead hood indicated generally at 28. It will be seenthat the body 5 of viscous liquids or heavy slurries is subject tocontinuous diminution as a function of the processing of this body andthat it is desirable to distributively feed the viscous liquids andheavy slurries to this body in such manner as to insure a uniformcomposition thereof.

The distributing feeder forming the subject of the present invention isshown as comprising a non-rotating outer horizontal pipe 25 arrangedabove the body or pool 5 in the valley or trough |4 between the drums l0and II and extending longitudinally thereof. This outer non-rotatinghorizontal pipe is provided along the lower part of its periphery with aseries of openings 2.6 extending in a straight line longitudinallythereof for a distance equal to the length of the drums over which thisseries is arranged. Within this outer non-rotating pipe 25 is closelyfitted an inner revolving pipe 28 provided with a. serpentine series ofopenings 29 arranged in a helix which, in the form of the inventionshown in Figs. 1-4, forms one convolution. Each of these openings 29 isarranged to register with a corresponding opening 26 of the non-rotatingouter pipe 25.

The revolving inner pipe 29 projects outwardly from the non-rotatingouter pipe through a stuffing box 30 on the corresponding end of theouter non-rotating pipe 25 and is secured to a drive shaft 3| journalledin a bearing 32 mounted on the corresponding end head 6 of the dryer.The connection between the inner revolving pipe 28 and the drive shaft3| is shown as comprising a solid extension 33 of the shaft 3| fittinginto the inner revolving pipe 28 and secured thereto by a cross bolt 34.The mounting for the bearing 32 is shown as comprising a bracket 35mounted on the base 36 for a variable speed transmission 38 and motor39, this base 36 being in turn mounted on the end head 6 of the dryer.

The drive shaft 3| is shown as connected with the variable speedtransmission 38 through a flexible coupling 40 and the drive motor 39 isshown as being directly connected with the case of this variable speedtransmission. It will be seen that the motor 39, through this variabledrive speed transmission 38 and flexible coupling 40, rotates the shaft3| in the bearing 32, this, in turn, rotating the inner revolving pipe28 within the outer non-rotating pipe 25. It will further be seen thatthe speed of rotation of this inner revolving pipe 28 can be regulatedby adjustment of the variable speed transmission 38.

The end of the non-rotating outer pipe 25 opposite from its simfling box38 projects from the corresponding end of the inner revolving pipe 28and this projecting end is mounted on the end head 7 of the dryer insuch manner as to provide longitudinal adjustment of this outernonrotating pipe 25 with reference to the revolving inner pipe 28 andthereby adjust the degree of registry of the openings 29 and 26 andhence the effective size thereof. For this purpose to this projectingend of the non-rotating outer pipe 25 is welded a depending verticalcross plate or bracket 42 which is provided with vertical slots 43.Bolts 44 extend through these slots into the vertical leg of an L-shapedsliding bracket 45. The lower horizontal leg of this L-shaped slidingbracket 45 is provided with slots 46 extending lengthwise of the outernon-rotating pipe 25, and vertical stud screws 48 extend through theseslots. These vertical stud screws 48 project upwardly from a base 49mounted on the end head I of the dryer and the outer end of this base 49is provided with an upstanding flange 50 which rotatably supports anadjusting screw 5|. This adjusting screw 5| is mounted in a threadedhole 52 in the flange 50 so that upon turning this screw through itshand wheel 53 it is moved longitudinally. The opposite end of this screwextends through an unthreaded hole in the up standing leg of the bracket45 and is provided with a pair of collars 54 on opposite sides of thisupstanding leg so that longitudinal movement of the screw 5| effectsmovement of the bracket 45 on the base 49 longitudinally of thenon-rotating outer pipe 25.

The end of the outer non-rotating pip 25 op-. posite from its stuffingbox 38 i connected through a valve 55 with a feed line 58. Since thenon-rotating outer pipe 25 is longitudinally adjustable, this feed line56 is shown as being in the form of a flexible conduit, although it willbe understood that it could be a rigid pipe with a stuffing box similarto the stufling box 30 to 5 permit such longitudinal adjustment of thenonrotating outer pipe 25.

The viscous liquid or heavy slurry to be dried is supplied under a.comparatively low pressure from the feed line 56, this slurry or liquidpassing through the valve 55 into the adjacent open end of the revolvinginner pipe 28. The opposite end of this inner revolving pipe 28 isblocked by the extension 33 of the drive shaft 3| and hence this slurryor liquid can only escape through such holes 29 of the revolving innerpipe 28 which at this time are in register with the corresponding holes26 of the non-rotating outer pipe 25. Since only one pair of these holes29 and 26 can be in full register at any one time it will be seen thatthese holes 29 and 26 of the inner revolving and outer non-rotatingpipes 25 and 28 can be made comparatively large and that a full flow offeed liquid or slurry is through these registering holes. The innerrevolving pipe 28 is being rotated through its connection with the driveshaft 3|, this drive shaft being driven through the flexible coupling40, variable speed transmission 38, and motor 39. As this revolvinginner pipe 28 so rotates, the pair of holes 29 and 26 in full registerwith each other are brought out of register and the next succeeding pairof holes 29 and 26 are brought into full register. This successiveregistry of each of the series of holes 29 and 26 continuesprogressively along the full length of the series of holes wherebysuccessive drops or amounts of the feed liquid or slurry areprogressively dropped into the pool 5 of liquid contained in the troughor valley H between the drums I and l I the full length thereof in theform of a discontinuous linear curtain of falling drops. When the lastholes of the two series pass out of register with each other the firstholes thereof come into register and hence the progressive discharge ofsuccessive amounts of the slurry or liquid from one end' of the space orvalley between the drums I 3 and II is repeated as long as the innerrevolving pipe 28 is rotated.

The effective size of the openings 29, 26 can readily be adjusted inaccordance with the amount of solids in the slurry or the viscosity ofthe liquid. Such adjustment is also desirable if the head on the feedliquid varies as when the liquid is supplied by gravity. To effect suchadjustment all that is required is to turn the hand screw 5| in acorresponding direction. Such turning move this hand screwlongitudinally relatively to the base 49 and accordingly moves thesliding L-shaped bracket 45 in a corresponding direction. This, throughthe depending plate or bracket 42 secured to the outer non-rotating pipe25, adjusts the outer non-rotating pipe in a corresponding direction.Accordingly the openings 29 and 26 can be adjusted to come into fullregister as the inner revolving pipe 28 rotates relative to the outernon-rotating pipe 25, or they can be adjusted to come into register inany desired degree.

Intervals between discharge through each of the openings 26 of the outernon-rotating pipe 25 can be regulated by control of the speed at whichthe inner revolving pipe 28 revolves. This is, of course, efiectedthrough the variable speed transmission 38. This inner revolving pipe 28can be provided with openings in more than one spiral if necessary toobtain discharge at more than one point at the same time. This innerpipe can also, of course, be made hollow over its entire length topermit continuous circulation of horizontal pipes the feed liquidthrough this pipe. In such event,

instead of the stub shaft 3| and flexible coupling 40 a suitable gearwould be keyed to the inner pipe 28 and driven from the variable speedtransmission 38.

As indicated, the distributing feeder is particularly applicable tohandling heavy liquids and slurries. Excellent results have beenobtained with starch slurries with an apparent viscosity of 500-9750centipoises with pressures of only 1-10 pounds per square inch,revolving the inner pipe 28 at from 20 to 40 revolutions per minute. Ithas also been found that the heavier the slurry or the greater theviscosity of the liquid, the wider the range over which the rate ofdischarge can be varied. When feeding starch or flour slurries to adouble drum dryer, the present distributing feeder is of particularbenefit because the starch gelatinizes n contact with the hot drums andforms a heavy paste which does not mix readily with the fresh feedslurry. Accord.- ingly, with such material exact uniformity and feedingat uniform intervals is particularly essential. It will be understoodthat one distributing feeder can be mounted above the center of thevalley or trough l4 between the drums l0 and II, as above described, orthat two such distributing feeders can be employed, one above the top ofeach of the drums l0 and II It will also be seen that instead ofproviding the non-rotating outer pipe 25 and the inner revolving pipe 28with a series of holes, the revolving pipe can be provided with ahelical slot although in this case the adjustability of the effectivesize of the discharge opening would be lost. Such a modification of theinvention is illustrated in Fig. 5 in which the inner revolving pipe 28ais shown as provided with a helical slot 29a. instead of the helicalseries of openings 29. It will also be understood that the innerrotating pipe 28 could be made stationary with a longitudinal series ofopenings in the lowest part of its periphery and that'the outer pipe 25could be made to revolve with a helical slot or a series of openingsarranged in helix.

From the foregoing it will be seen that the present invention provides amethod and apparatus for feeding viscous liquids and heavy slurrieswhich is of extremely simple and inexpensive operation and constructionand which is, in effect, provided with a large through opening whichtravels lengthwise of the horizontal pipes so' as to feed such heavyliquids and slurries with a high degree of uniformity over an extendedarea. It will also been seen that the feeder can be readily adjusted asto the effective size of its discharge openings to suit the viscosity orhead of the feed liquid and can also be readily regulated to control theintervals between the discharge of the liquid at each point along thefeeder.

I claim:

1. 5.. distributing feeder for viscous liquids and heavy slurries,comprising a pair of generally revolvably fitted one within the otherand each having an end projecting beyond the other pipe, meansnon-rotatably supporting one of said pipes and connectedto theprojecting end thereof, said one of said pipes having the lower part ofits periphery provided with at least one opening extending a substantialdistance along the length thereof and the other of said pipes beingprovided with at least one opening also extending a substantial distancealong the length thereof and arranged to register with a substantialextent of'the length of said first opening, a stufiingbox secured to theend of said outer of said pipes fromwhich the inner of said pipesprojects and surrounding said projecting end of said inner of saidpipes, a continuously rotating driver connected to said projecting endof said; other of said pipes and arrangedto rotate continuously saidother of said pipes relative to said one or said pipes, and meansconnected to said projecting end of said one of said pipes and arrangedto supply the material to be distributed to the inner of said pipes,said opening in said other of said pipes being of serpentine formwhereby limited portions of said openings are in register at any onetime to provide a. through opening traveling lengthwise of said pipes assaid pipes rotate relative to each other.

2. A distributing feeder for viscous liquids and heavy slurries,comprising a pair of generally horizontal pipes revolvably fitted onewithin the other and each having an end projecting beyond the otherpipe, means non-rotatably supporting the outer pipe and connected to theprojecting end thereof, said outer pipe having the lower part of itsperiphery provided with at least one opening extending a substantialdistance along the length thereof and the inner pipe being provided withat least one opening also extending a: substantial distance along thelength thereof and arranged to register with a substantial extent of thelength or said first opening, a stufiing box: secured to the end of saidouter pipe from which the inner pipe projects and surrounding saidprojecting end: of said inner pipe, a bearing supporting the projectingend of said inner pipe, a continuously rotating driver connected to theprojecting end of said inner pipe and arranged to rotate continuouslysaid inner-pipe, and means connected; to said projecting end of saidouter pipe and arranged to supply the material to be distributed to theinterior of the inner pipe, said opening in said inner pipe being ofserpentine form: whereby limited portions of said openings are inregister at any onetime to provide a through opening travelinglengthwise of said pipes as said inner pipe rotates.

3. A distributing feeder for viscous liquids and heavy slurries,comprising a pair of generally horizontal pipes revolvably fitted onewithin the other, an adjusting mounting for one of said pipes and.permitting it to be adjusted lengthwise of its axis but holding itagainst rotation, a journal mounting tor the other of said pipes andpermitting its rotation but holding it against lengthwise movement, saidone of said pipes having the lower part of its periphery provided witha'series of. openings extending a substantial distance along the lengththereof and said other of said pipes being provided with a series ofopenings also extending a substantial distance along the length thereofand having its openings arranged to register with the openings of saidfirst series as said pipes rotate relative to each other, the openingsof said two series being of such size and arrangement that adjustment ofthe longitudinal position of said one of said pipes adjusts theeffective size of both series of openings, a continuously rotatingdriver, means connecting said continuously rotating driver with saidother of said pipes to rotate continuously said other of said pipesrelative to said one of said pipes and means arranged to supply thematerial to be distributed to the interior of the inner of said pipes,said series of openings in 8 said other of said pipes being ofserpentine form whereby a limited number of the two series are inregister at any one time to provide a limited number of through openingstraveling lengthwise of the pipes as the pipes rotate relative to eachother.

4. A distributing feeder for viscous liquids and heavy slurries,comprising a, pair of generally horizontal pipes revolvably fitted onewithin the other, an adjusting mounting for one of said pipes andpermitting it to be adjusted lengthwise of its axis but holding itagainst rotation, a journal mounting for the other of said pipes andpermitting its rotation but holding it against lengthwise movement, saidone of said pipes having the lower part of its periphery provided with aseries of openings extending a substantial distance along the lengththereof and said other of said pipes being provided with a series ofopenings also extending a substantial distance along the length thereofand having its openings arranged to register with the openings of saidfirst series as said pipes rotate relative to each other, the openingsof said two series being of such: size and arrangement that adjustmentof the longitudinal position of said one of said pipes adjusts theefiective size of both series of openings, a continuously rotatingdriver, means connecting said continuously rotating driver withsaid'other of said pipes to rotate continuously said other of said pipesrelative to said one of said pipes, means connected with said one ofsaid pipes and arranged to supply the material to be distributed to theinterior of the inner of said pipes, and a stufiing box secured to oneend of the outer of said pipes and surrounding the corresponding part ofthe inner of said pipes, said series of openings in said other of saidpipes being of serpentine form whereby a. limited number of the twoseries are in register at any one time to provide a limited number ofthrough openings traveling lengthwise of the pipes as the pipes rotaterelative to each other.

5. A distributing feeder for viscous liquids and heavy slurries;comprising a pair of generally horizontal pipes revolvably fitted onewithin the other and each having an end projecting beyond the: otherpipe, an adjusting mounting for the projecting end of one of said pipesand permitting it tobe adjusted lengthwise of its axis but holding itagainst rotation, a journal mounting for the projecting end of the otherof said pipes and permitting its rotation but holding it'againstlengthwise movement, said one of said pipes having the lower part of itsperiphery provided with a series of openings extending a substantialdistance along the length thereof and saidother of said pipes beingprovided with a series of openlngs also extending a substantial distancealong the length thereof and having its openings arranged to registerwith the openings of said first series as the pipes rotate relative toeach other, the openings of said two series being of such size andarrangement that adjustment of the longitudinal position of said one ofsaid pipes adjusts the effective size of both series of openings, asmiling box secured to the end of the outer of said pipes from which theinner of said pipes projects and surrounding said projecting end of saidinner of said pipes, a continuously rotating driver connected to theprojecting end of said other of said pipes and arranged to rotate COD.-tinuously said other of said pipes relative to said one of said pipes,and a flexible conduit connected to said projecting end of said one ofsaid pipes and arranged to supply the materia1 to be distributed to saidinner of said pipes, said series of openings in said other of said pipesbeing of serpentine form whereby a limited number of the openings of thetwo series are in register at any one time to provide a limited numberof through openings traveling lengthwise of the pipes as the pipesrotate relative to each other.

6. In the processing of a body of viscous liquids and heavy slurrieswhich body has an extensive upper surface and which processing involvesthe continuous diminution of said body, the method of feeding saidviscous liquids and heavy slurries to said body to insure substantiallyuniform composition of all parts of said body, which comprisescontinuously releasing from a substantial distance above said surfaceand at substantially uniform time intervals a succession ofsubstantially uniformly spaced separate drops of substantially uniformsize along a horizontally extending line to provide a discontinuouslinear curtain of drops falling by gravity into said body linearly alongsaid upper surface thereof, and regularly repeating said last step tofeed said viscous liquids and heavy slurries at a rate corresponding tothe continuous diminution of said body in the processing thereof.

7. The process as set forth in claim 6 wherein said amounts are releasedfrom a supply maintained under pressure.

JOHN WALTON ANGSTADT.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,255,156 Goff Feb. 5, 1918 1,410,312 Huffman Mar. 21, 1922

